Toxins (esp. CagA and VacA)CagA was the first protein antigen identified as a marker for the more evil type of H.pylori. cagA is one of about 30 genes in Cag pathogenicity island (cagPAI). These genes form a secretion system which injects CagA protein into cells where it causes disorganised cellular structure due to "growth factor like" effects.
VacA is a toxin which causes vacuolation of epithelial cells (bubbles within) when H.pylori attaches. VacA is a activated in acid to form a membrane pore which causes cells to become leaky, especially to urea. It also suppresses some of the immune response allowing H.pylori to persist. Moderators:Toni, barjammar, stomach

Genomics of HelicobactersOne of the first bugs to be sequenced, H.pylori has a small genome (1.6 MD) befitting its lifestyle in a hostile acidic mucosal niche. Of the 1500 genes, 750-1000 are essential, the others are different in each strain. Hp has an "open pan-Genome" which means the more strains you look at the more genes you will find - i.e. you will never have a complete set of all its possible genes! Moderators:Toni, barjammar, stomach

Animal Models of HpThe initial animals infected with human Hp were germ free piglets. After that beagle puppies, pigs, mice, cats and, best of all, Mongolian Gerbils. The latter animals develop ulcers and stomach tumours in the presence of salt and carcinogens - similar to humans. There is much work to be done in this area. Moderators:Toni, barjammar, stomach

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